Well let's see.
Ecco the Dolphin probably doesn't count as an RPG nor does Goldeneye. Magic the Gathering was never an RPG. Although Ube and others might object, I would have to say that Diabl II was my 1st. And if DII doesn't count, then it would be NWN.
The question is not, Can they reason? nor, Can they talk? but, Can they suffer?